Although artificial or prosthetic limbs have been around for well over a century, much about them has not changed. The residual limb (also called the stump) of the user is generally secured to the prosthesis via a socket (also called the receiver) or the like engaging same. Straps have been used in the past to secure continued proper engagement of the residual limb to the prosthesis, but the straps can be uncomfortable and ineffective. Other systems have used a vacuum to retain the limb in place, but such a system only works as long as a good seal is in place, and variations in the size of the limb can result in loss of a seal.
It is believed the most popular means of facilitating the residual limb in the receiver of a prosthesis is by use of a tubular stocking or the like also called a “Jersey Sheath” “stump stocking”, or “donning sock”, which has generally been formed of elastic textile material which conforms to the residual limb and engages same when placed thereupon.
In use, a strap is provided at the end of the stocking. The stocking is pulled upon the residual limb to envelope the end of said limb and a length up said limb. A strap (also may be referenced as a lanyard) or the like is mounted to the end of the stocking at the end of the residual limb. The limb is placed into the socket and the free end of the strap is threaded through a slot, generally at the base of the socket, and the strap is then pulled to urge the residual limb (enveloped by the stocking) firmly into the base of the socket, where it is secured in place.
A problem with this system is that the wearer of the prosthetic limb may lack the strength, flexibility or dexterity to adequately pull the strap so as to properly secure the residual limb into the socket. Such users may be otherwise disabled, physically weak or lack the ability to firmly grasp the strap by hand.
Accordingly, various systems have arisen over the years to facilitate pulling of leg stocking with residual limb into the socket of the prosthesis, such as a cable and pulley system (U.S. Pat. No. 2,666,927), or a motorized, winch-like pulling apparatus (see U.S. Pat. No. 3,922,727 or 5,203,791), a roller system (U.S. Pat. No. 4,038,701), ratcheting mechanism (U.S. Pat. No. 5,326,351), or cable/spool system (U.S. Pat. No. 6,797,008).
A commonality of these systems is that they tend to be cumbersome, unnecessarily complicated, expensive, and have not been embraced by the public, Even today, it is believed that new wearers of these prosthetic limbs tend to be generally taught to use their hands in pulling the straps to urge the residual limb into the prosthetic socket, implicitly suggesting that the prior art systems were of limited usefulness.
Accordingly, there continues to exist a long felt, but unresolved need for a system for pulling a strap for a leg stocking for securing same into the socket of a prosthetic limb which is safe, effective, easy to use, and relatively inexpensive.